I don't believe this is possible. I'm pretty sure if you go into notification center and disable sounds for apps, it also disables the vibrate function.

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Your right because I disabled sounds and although it was set to vibrate only it wouldn't vibrate and when I reactivated the sounds switch the vibrat came on but it wasn't vibrate only it was vibrate with a sound lol I don't know why it says vibrate only
If it doesn't ( ah well I'll have to se if there's a third part
Y programme. Thanks anyway for the reply.

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